PC133 ram is the same thing as PC2100 ram right?

[Hammyton]

They both run at the same clock speed and such... meaning one could easily be advertised as being the other?

 

[MustISO]

One is SDRAM one is DDR.

 

[Gamingphreek]

Originally posted by: MustISO
One is SDRAM one is DDR.

Exactly. DDR of them sends/recieves data on the rise and the fall of the clock (sin wave), whereas SDR sends it on the rise of each clock.

That is why you double the clock speed of DDR.

-Kevin

 

[JustAnAverageGuy]

No.

 

[WT]

Well, no. PC133 is 168 pin RAM single memory configuration, whereas PC2100 is 184 pin memory using dual memory configuration (data flows in both the up and down memory clock cycles). Also, SDRAM has two notches in it, and DDR SDRAM has only one.

 

[justly]

While they both run at 133MHz they are not interchangable and should not be confussed. PC133 should only be used to describe single density memory, while PC2100 may sometimes be called DDR133 but not PC133.

 

[Googer]

Originally posted by: MustISO
One is SDRAM one is DDR.

DDR is SDRAM, they are one and the same. 168 Pin DIMMS transmit one signal per clock cycle, also know these days as SDR (Single Data Rate). 184 Pin DIMMS transmit two signals per clock cycle at 133MHz and are known a DDR (Double Data RATE). They call it PC2100 because 2,100 is the number of megabytes that can be transfered in one second, PC133 SDR can only send about 1,000 to 1,050 Megabytes per second.

Dont expect to be able to run DDR on an SDR (PC133/100/75/66) motherboard for two reasons-
[*] The Pin Count for PC133/100/66 is differant than PC 2100 DDR. Also there are notches in both of the DIMMS, that prevent you from installing it in an unsupported socket.

[*] The other reason is you need a memory controller that will support DDR, since it is newer than SDR PC133 it is highly unlikely that your motherboard will run DDR. But there are some Exceptions though, certain Socket A motherboards have memory controllers that work with DDR and SDR.

Also if your motherboard only supports PC2100 aka DDR133 it is safe and ok to run DDR400 aka PC3200 (200 MHz). It should work ok 99.99% of the time. Your motherboard will only run it at 133MHz. The only benefits of using faster DDR than what your motherboard will support is that you can run faster memory timings and overclock it to a much higher frequency with out having to tweak the latency much.


aka= Also Known As.